Bingham, Levis and Rubin (unpubl.) found cloned segments in a hybrid phage clone library made from D. melanogaster DNA that showed very weak DNA sequence homology to the white locus region from this same organism. We have shown that most or all of these cloned segments derive from distal 3A on the polytene chromosome map (the region containing the zeste locus, a locus that interacts genetically with the white locus). We are currently analyzing this phenomenon in more detail.